Which type of motor is used in cranes?
Conventional AC operated crane drives use slip ring induction motor whose rotor windings are connected to power resistance in 4 to 5 steps by power contactors.
Which motor is most suitable for crane drive operation 1 point?
1. Which DC motor is generally preferred for cranes and hoists? Explanation: DC series motor is used where high starting torque is required, thus in cranes and hoists DC series motor is used widely.
Which motor is preferred for use in crane?
Synchronous motor. For crane travel, trolley travel and boom hoist of traveling crane requires high starting torque and constant speed in operation. Hence slip ring induction motor is preferred.
Do cranes use DC motors?
Many older cranes operate on DC power because when those controls were built, DC was easier to supply and provided the power load necessary to drive large, robust pieces of equipment. But as technology advanced AC power also advanced.
Which motor is used in lift?
Lifts are preferred by AC slip ring or DC compound motor. In case of single phase installation, the commutator motors are preferred. Variable Frequency drive electronic controls are used in the latest lift designs.
Which motor is not suitable for crane application?
Squirrel cage induction motor has the problem of low starting torque due to low resistance. Therefore, they are not suitable for applications like crane or lifts. On the other hand, a slip ring induction motor is also similar to the normal Squirrel cage induction motor.
Why is the DC motor preferred over AC motor?
Because DC motors have higher starting torque compared to AC motors, they are preferred for applications like electrical traction. They are considered ideal for dealing with heavy loads for starting conditions in machines such as locomotives and cranes.
What is the speed of dc motor?
DC controls adjust speed by varying the voltage sent to the motor (this differs from AC motor controls which adjust the line frequency to the motor). Typical no load or synchronous speeds for an AC fractional horsepower motor are 1800 or 3600 rpm, and 1000-5000 rpm for DC fractional hp motors.
Which motor has the poorest speed control?
1. Which of the following DC motor has the poorest speed control? Explanation: DC series motor at no load condition gives infinite speed ideally. Practically it will damage all the armature circuit.
Which DC motor is preferred for constant speed?
Explanation: Rotary compressor generally demand constant speed operation throughout the load. Sometimes, DC machines are not able to produce constant speed throughout the process hence, synchronous machine is used. 4.
Which motor is preferred for quick speed reversal?
For quick speed reversal the motor preferred is. dc motor. squirrel cage induction motor. slip-ring induction motor.